Fixed 49.9 ohm impedance output. The real output voltage of the device is not necessarily the same as the indicated output voltage of the device because there is a 50 ohm resistor in series with the output. This is done so that the user can have adequate transmission line termination on a 50 ohm coaxial cable, as well as being a rudimentary short circuit protection mechanism. You can set in software the impedance of the load you are driving so that the displayed voltage settings match the voltage present in the load. In earlier firmware versions, there were High-Z and 50 ohm impedances available. In more recent firmware versions (which?) the user can select any impedance from 50 ohm to 1k ohm and high-Z. Note that this only affect the displayed value. The internal output impedance is still 50 ohms, and there is still a voltage drop across that resistor, a voltage drop.

Ch1 can output up to 20V peak to peak (it goes from -10V to +10V), Ch2 can only go up to 6V pk-pk. Both have the fixed 49.9 ohm impedance, but because of the higher voltage output, Ch1 uses an array of 4 resistors, as seen on the images below.

Display/frontpanel:

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Power supply:

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Photos

Device

Teardown

Digital parts

Analog parts

Display / frontpanel

Power supply

Protocol

There are two possible PC connectivity methods that can be selected in the SDG1010 menu, which have different USB VID/PID pairs:

"Raw USB" (this is what the vendor PC software uses): f4ed:ee37

"USBTMC": f4ed:ee3a

Additionally, there are apparently GPIB and Ethernet options, but those are not available in the "standard" device. It's unclear if/where devices with those options can be bought, maybe only the rebranded LeCroy devices have them (?)

TODO: Details.
USBRAW connectivity is not possible on a Windows 8 platform, because of driver signature enforcement (details). Additionally, there are no drivers provided by Siglent for platforms other than Windows. Obviously, USBTMC is the method to use for universal communication with this device.